Nature Communications
·
2024
·Vol. 15
·期 1
·1-14
·
IF 14.7
Wei Xinlei,Yang Xue,Hu Congcong,Li Qiangzi,Liu Qianqian,Wu Yue,Xie Leipeng,Ning Xiao,Li Fei,Cai Tao,Zhu Zhiguang,Zhang Yi-Heng P. Job,Zhang Yanfei,Chen Xuejun,You Chun
In vitro biotransformation (ivBT) facilitated by in vitro synthetic enzymatic biosystems (ivSEBs) has emerged as a highly promising biosynthetic platform. Several ivSEBs have been constructed to produce poly-3-hydroxybutyrate (PHB) via acetyl-coenzyme A (acetyl-CoA). However, some systems are hindered by their reliance on costly ATP, limiting their practicality. This study presents the design of an ATP-free ivSEB for one-pot PHB biosynthesis via acetyl-CoA utilizing starch-derived maltodextrin as the sole substrate. Stoichiometric analysis indicates this ivSEB can self-maintain NADP + /NADPH balance and achieve a theoretical molar yield of 133.3%. Leveraging simple one-pot reactions, our ivSEBs achieved a near-theoretical molar yield of 125.5%, the highest PHB titer (208.3 mM, approximately 17.9 g/L) and the fastest PHB production rate (9.4 mM/h, approximately 0.8 g/L/h) among all the reported ivSEBs to date, and demonstrated easy scalability. This study unveils the promising potential of ivBT for the industrial-scale production of PHB and other acetyl-CoA-derived chemicals from starch.
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PubMed
高影响因子
WORLD JOURNAL OF MICROBIOLOGY & BIOTECHNOLOGY
·
2024
·Vol. 40
·期 6
·1-13
·
IF 4
Zhao Siji,Yin Ruya,Zhang Mengwei,Zhai Ziqi,Shen Zhen,Mou Yan,Xu Dan,Zhou Ligang,Lai Daowan
The endophytic fungus Berkleasmium sp. Dzf12 that was isolated from Dioscorea zingiberensis , is a proficient producer of palmarumycins, which are intriguing polyketides of the spirobisnaphthalene class. These compounds displayed a wide range of bioactivities, including antibacterial, antifungal, and cytotoxic activities. However, conventional genetic manipulation of Berkleasmium sp. Dzf12 is difficult and inefficient, partially due to the slow-growing, non-sporulating, and highly pigmented behavior of this fungus. Herein, we developed a CRISPR/Cas9 system suitable for gene editing in Berkleasmium sp. Dzf12. The protoplast preparation was optimized, and the expression of Cas9 in Berkleasmium sp. Dzf12 was validated. To assess the gene disruption efficiency, a putative 1, 3, 6, 8-tetrahydroxynaphthalene synthase encoding gene, bdpks , involved in 1,8-dihydroxynaphthalene (DHN)-melanin biosynthesis, was selected as the target for gene disruption. Various endogenous sgRNA promoters were tested, and different strategies to express sgRNA were compared, resulting in the construction of an optimal system using the U6 snRNA-1 promoter as the sgRNA promoter. Successful disruption of bdpks led to a complete abolishment of the production of spirobisnaphthalenes and melanin. This work establishes a useful gene targeting disruption system for exploration of gene functions in Berkleasmium sp. Dzf12, and also provides an example for developing an efficient CRISPR/Cas9 system to the fungi that are difficult to manipulate using conventional genetic tools.
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PubMed
高影响因子
CHEMICAL RESEARCH IN CHINESE UNIVERSITIES
·
2018
·Vol. 34
·期 4
·665-669
·
IF 1.248
Lyu Linlin,Jiang Xiaojun,Jia Lian,Ai Tian,Wu Hang
To increase the adsorption capacity of the Corylus heterophylla Fisch(HS) for Pb 2+ , HS was chemically modified using NaOH aqueous solution and 95% ethanol and was labeled as SHS; then SHS was chemically modified using mercaptoacetic acid. The SHS modified with mercaptoacetic acid(MHS) was characterized using FTIR, SEM, and XPS. The results indicated that the —SH group was present on MHS, and after Pb 2+ adsorption, the absorption value of the characteristic peak of the —SH group decreased. The adsorption and desorption properties of this functionalized material were investigated as well as the influences of parameters, such as pH value, type of desorption reagent, dosage, flow rate and maximum sample volume. The Pb 2+ adsorption of MHS reached a maximum with pH>5. The experimental data of Pb 2+ adsorption using MHS were fitted using the Langmuir isothermal adsorption model, and a maximum adsorption capacity of 61.54 mg/g was obtained. This was much higher than the adsorption capacity of SHS before modification with the thiol group. After adsorption, MHS was desorbed using a 0.2 mol/L HCl solution, and the percent of desorption was higher than 99%. MHS was used as a solid-phase extractant in the analysis and determination of Pb 2+ content in food and water samples, and the enrichment times achieved 150-fold.
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高影响因子
MICROCHIMICA ACTA
·
2018
·Vol. 185
·期 8
·1-9
·
IF 5.705
Liu Li,Zhao Guanhui,Li Yueyuan,Li Xuan,Dong Xue,Wei Qin,Cao Wei
The authors describe a voltammetric immunoassay for the carcinoembryonic antigen (CEA). It is based on the use of a self-assembled magnetic nanocomposite as multifunctional signal amplification platform. The core of the nanocomposite consists of Fe 3 O 4 microspheres, and the shell of zirconium hexacyanoferrate loaded with gold nanoparticles (AuNPs@ZrHCF@Fe 3 O 4 ). The material was synthesized by an electrostatic self-assembly process which is caused by the strong interaction between cyano groups and AuNPs. The surface of the Fe 3 O 4 microspheres was functionalized with amino groups to facilitate the immobilization of ZrHCF which acts as an electron mediator. The nanocomposite was placed on a glassy carbon electrode which then displays noteworthy electrocatalytic activity toward the reduction of hydrogen peroxide (H 2 O 2 ). The AuNPs serve as a support for the immobilization of antibodies by the interaction between AuNPs and amino groups on antibodies to construct a covalent Au-N bond. This facilitates electron transfer on the electrode surface using H 2 O 2 as the electrochemical probe. Square wave voltammetry (measured typically at +0.2 V vs. SCE) was carried out to record the electrochemical behavior. Under the optimal conditions, a response is linear in the 0.5 pg·mL −1 to 50 ng·mL −1 CEA concentration range, and the detection limit is as low as 0.15 pg·mL −1 (S/ N = 3). The method is selective, highly stable and acceptably reproducible.
A self-assembly magnetic nanocomposite for voltammetric immunoassay of CEA. GCE glassy carbon electrode; Au NPs gold nanoparticles; ZrHCF zirconium hexacyanoferrate; CEA carcinoembryonic antigen; Anti-CEA CEA antibody; BSA bovine serum albumin; SWV square wave voltammetry. A high sensitive voltammetric immunoassay method has been used for detecting CEA, It is based on a self-assembled magnetic nanocomposite (Au NPs@ZrHCF@Fe 3 O 4 ) as multifunctional signal amplification platform.
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高影响因子
Scientific Reports
·
2017
·Vol. 7
·期 1
·1-11
·
IF 4.259
Zhao Jiangtao,Zhang Peng,Wang Zhuo,Zhang Shijie,Gao Hongqing,Hu Junhua,Shao Guosheng
In the field of photocatalysis, the high-charge recombination rate has been the big challenge to photocatalytic conversion efficiency. Here we demonstrate the direct evidence of multichannel-improved charge-carrier mechanism to facilitate electron-hole transfer for raising photocatalytic H 2 evolution activity. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and UV-Vis diffuse reflectance spectroscopy (DRS), were used to characterize the as-fabricated samples. The result shows that the present design of Au/Pt nanoparticles (NPs) decorated one-dimensional Z-scheme TiO 2 /WO 3 heterostructure composite nanofibers have been fabricated, which even exhibited excellent light absorption in the visible region and greatly enhanced photocatalytic activities on H 2 generation comparing with pure TiO 2 , TiO 2 /WO 3 and Pt/WO 3 /TiO 2 nanofibers. This greatpromotion is mainly on account of the photosynthetic heterojunction system, which include the surface plasmon resonance (SPR) of Au nanoparticles, low overpotential of Pt nanoparticles, and more importantly, the one-dimensional multichannel-improved charge-carrier photosynthetic heterojunction system with Pt as an electron collector and WO 3 as a hole collector. Transferring photoinduced electrons and holes at the same time, leading to effective charge separation was directly proved by ultraviolet photoelectron spectroscopy, electrochemical impedance spectroscopy, photocurrent analysis and incident photon-to-electron conversion spectrum.
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高影响因子
BULLETIN OF MATERIALS SCIENCE
·
2020
·Vol. 43
·期 1
·1-6
·
IF 1.392
Li Dan,Wang Yuxiang,Guo Meng,Song Mingjun,Ren Yang
Ethylene glycol (EG)-based hybrid nanofluids containing graphene oxide–silver nanosheets (GO–Ag) were simply prepared without using any surfactant. The graphene oxide–silver composites were characterized using X-ray diffraction analysis, transmission electron microscope, infrared and UV–visible spectroscopy. The stability of GO–Ag nanofluids was estimated by UV–visible spectroscopy. The GO–Ag/EG hybrid nanofluids has good stability without significant sedimentation for 60 days. A few thermophysical properties of GO–Ag/EG nanofluids with 0.1, 0.2 and 0.3 wt% nanosheets were analysed experimentally at different temperatures ranging from 20 to 50°C.
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高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2022
·Vol. 57
·期 5
·3613-3628
·
IF 4.682
Guo Zijiao,Li Yue,Lu Zan,Chao Yunfeng,Liu Wei
Abstract As interest in smart textiles grows, fiber-based supercapacitors are gaining attention as promising devices for powering wearable electronics. Herein, we have demonstrated a two-step manufactured hybrid fiber with excellent energy storage properties. Anhydrous MXene (Ti 3 C 2 T x ) sheets are primarily spun in synergy with liquid crystal carbon nanotubes (CNTs) to produce a continuous fiber as a promising electrode material, which solves the problem of poor rate capability owing to the sheet re-stacking of MXene. MnO 2 @MXene/CNT fibers are subsequently prepared by electrochemical deposition with controlled time. The optimal content of MXene (10 wt%) and a perfect thickness of the MnO 2 layer (4 μm) are testified to achieve an excellent capacitance of 371.1 F cm −3 in three-electrode system, which is about 200% and 1800% higher than that of 10 wt%-MXene/CNT and CNT fiber electrode, respectively. Symmetric fiber supercapacitor is assembled by paralleling two fibers with LiCl/PVA gel electrolyte, manifesting a superior cycling stability of 86.3% after 10000 cycles. Graphical Abstract Anhydrous MXene nanosheets and CNTs are incorporated by a high yield spinning technique to prepare continuous hybrid fibers as a conductive framework for MnO2 deposition, exhibiting stable and outstanding energy storage properties in supercapacitor.
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高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2018
·Vol. 53
·期 9
·6698-6706
·
IF 2.993
Gao Bingying,Yuan Guojun,Ren Lili
Abstract Aiming to develop universal, effective, and visually observable sensing nanomaterials for detecting concentrations of volatile organic compounds (VOCs), we fabricated a functionalized alumina aerogel sheet by embedding a chromatic conjugated polymer–polydiacetylene (PDA) in alumina aerogel pores, which underwent dramatic color changes upon exposure to different concentrations of VOCs. Taking the activated carbon as the example, we designed an air purification detection system by using the as-synthesized PDA-functionalized alumina aerogel sheets, which could give a definite indication from the changes of color. Overall, this study presents a simple and low-cost method to fabricate PDA-functionalized alumina aerogel sheet in which noncovalent interactions between the alumina aerogel sheet substrate and spin-coated PDA give rise to distinct chromatic properties after exposure to different concentrations of VOCs.
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高影响因子
Nano Research
·
2017
·Vol. 10
·期 5
·1794-1803
·
IF 7.354
Pan Jun,Wang Nana,Zhou Yanli,Yang Xianfeng,Zhou Wenyao,Qian Yitai,Yang Jian
High-capacity anode materials are highly desirable for sodium ion batteries. Here, a porous Sb/Sb 2 O 3 nanocomposite is successfully synthesized by the mild oxidization of Sb nanocrystals in air. In the composite, Sb contributes good conductivity and Sb 2 O 3 improves cycling stability, particularly within the voltage window of 0.02–1.5 V. It remains at a reversible capacity of 540 mAh·g –1 after 180 cycles at 0.66 A·g –1 . Even at 10 A·g –1 , the reversible capacity is still preserved at 412 mAh·g –1 , equivalent to 71.6% of that at 0.066 A·g –1 . These results are much better than Sb nanocrystals with a similar size and structure. Expanding the voltage window to 0.02–2.5 V includes the conversion reaction between Sb 2 O 3 and Sb into the discharge/charge profiles. This would induce a large volume change and high structure strain/stress, deteriorating the cycling stability. The identification of a proper voltage window for Sb/Sb 2 O 3 paves the way for its development in sodium ion batteries.
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高影响因子
CHROMATOGRAPHIA
·
2019
·Vol. 83
·期 1
·107-113
·
IF 1.552
Zhou Feng,Ren Xianghong,Du Siyan
Abstract Current methods for measurement of unsymmetrical dimethylhydrazine (UDMH) in wastewater suffer from a small detection range and complex pretreatment. In this study, ion chromatography (IC) with conductivity detection was used to directly analyze UDMH in wastewater, without any derivatization pretreatment, and the measurement range was as wide as 0.5–1000 μg·mL −1 . The effects of column temperature and sample pH on the detection were investigated. Furthermore, the chromatography conditions were optimized by combining the effects of different combinations of nitric acid, 2,6-pyridinedicarboxylic acid (PDCA), and methanesulfonic acid (MSA) on the analysis of mixed samples of UDMH and alkali metal ions. The linearity of the detected peak height ( H ) and peak area ( A ) versus UDMH concentration was studied at low, medium, and high concentrations. A good linear relationship was observed in the range of 0.5–1000 μg·mL −1 , especially for A , the relative standard deviation (RSD) and correlation coefficient ( R 2 ) of which were 0.077–1.653% and 0.9998–1.0000, respectively. In addition, the method showed good sensitivity with a limit of detection (LOD) of 0.05 μg·mL −1 and a limit of quantitation (LOQ) of 0.16 μg mL −1 . The precision and accuracy (expressed by recovery) were verified, where the RSD were less than 1.49% and 3.17%. Interference between hydrazines and alkali metal ions was discussed. Finally, actual UDMH samples were determined, confirming the applicability of the developed method for analyzing UDMH in wastewater during the degradation process. Graphic Abstract
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高影响因子
ANALYTICAL AND BIOANALYTICAL CHEMISTRY
·
2020
·Vol. 412
·期 19
·4725-4737
·
IF 3.637
Fu Han,Xu Wu,Wang Haixiang,Liao Shenghua,Chen Guitang
This study was based on the specific binding ability of magnetic molecularly imprinted polymers (MMIPs) combined with a high-performance liquid chromatography-fluorescence detector (HPLC-FLD) for the rapid determination of zearalenone (ZEN) in cereals. A novel magnetic molecularly imprinted polymer was prepared by surface imprinting technology. Warfarin was used as a virtual template, 3-aminopropyl triethoxysilane (APTES) was used as the functional monomer, and tetraethyl orthosilicate (TEOS) was used as the cross-linking agent. Analysis by a vibrating sample magnetometer (VSM), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) showed that MMIPs were prepared with a particle size about 450 nm, the imprinted molecular layer accounting for 10.7% of the total mass, and saturation magnetization of about 34.54 emu/g. The maximum adsorption capacity ( Q max ) of the thermodynamic and kinetic adsorption experiments were 13.90 mg/g and 8.71 mg/g, respectively. The Langmuir model showed that the binding sites were uniformly distributed on the surface of the MMIPs. The Scatchard analysis showed that MMIPs had two types of binding sites with Q max of 8.22 mg/g and 15.37 mg/g, respectively. In actual sample detection, the limit of detection (LOD) and limit of quantification (LOQ) were 0.4 ng/kg and 0.9 ng/kg, respectively. The sample recovery rate was 90.56–99.96%, the daytime stability was 1.35–2.87%. These results showed that MMIPs had good performance in selectively identifying ZEN and were suitable for determining ZEN in cereals.
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高影响因子
CHEMICAL PAPERS
·
2017
·Vol. 72
·期 1
·51-56
·
IF 1.258
Wei Mengyi,Qian Chao,Chen Xinzhi
Based on the recycling of NO
x
, the Cu(I)- and HNO 3 -catalyzed oxidation of 2-chloro-4-(methylsulfonyl)toluene to 2-chloro-4-(methylsulfonyl)benzoic acid has been developed with an excellent yield of 84.2% and a purity of 99.7%. The optimized reaction conditions (160 °C, oxygen pressure 1.5 MPa, HNO 3 concentration 25 wt%, HNO 3 : substrate 0.5:1) use 1.0 mol% CuI as catalyst. The dosage of HNO 3 in the new process is only 25% of the stoichiometric amount and 12.5% of the amount of the traditional process. The NO
x
emission is 5% amount of the traditional process. The oxidation of several additional toluene derivatives with comparable yields demonstrates the generality to these reaction conditions.
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高影响因子
危险品化学品经营许可证（带存储）